All Creatures of the Sea Lawful to Eat
[5:96] All fish of the sea are made lawful for you to eat. During pilgrimage, this may provide for you during your journey. You shall not hunt throughout the pilgrimage. You shall reverence GOD, before whom you will be summoned.
[5:97] GOD has appointed the Ka’bah, the Sacred Masjid,* to be a sanctuary for the people, and also the Sacred Months, the offerings (to the Sacred Masjid), and the garlands marking them. You should know that GOD knows everything in the heavens and the earth, and that GOD is Omniscient.
Footnote *5:97 The idol-worshiping Muslims have instituted two “Sacred Masjids” by consecrating the Prophet’s tomb. The Quran talks only about one Sacred Masjid.
This verse shows that all fish in the sea are lawful to eat. We do not see any prohibitions against shellfish or any other animals of the sea.
The Only Dietary Prohibitions*
[6:145] Say, “I do not find in the revelations given to me any food that is prohibited for any eater except: (1) carrion, (2) running blood, (3) the meat* of pigs, for it is contaminated, and (4) the meat of animals blasphemously dedicated to other than GOD.” If one is forced (to eat these), without being deliberate or malicious, then your Lord is Forgiver, Most Merciful.